Anal cancer is a serious disease that affects many. Early detection of anal cancer or pre-cancer is critical. Currently, testing is performed using a cotton or polyethylene terephthalate (PET) swab. The swab is inserted into the anus and the physician moves the swab from side to side while simultaneously rotating the swab about its longitudinal axis. The goal is to collect cells that can be either transferred to a liquid or to a slide to enable examination of the cells under magnification.
There are several disadvantages to the above-described procedure. Although the swabs collect cells well, it can be difficult to transfer those cells to a liquid or a slide because the cells tend to get trapped in the fibers of the swab. Furthermore, the sample technique is relatively complicated and is subject to great variability between physicians. As a consequence of these issues, the swab method has poor sensitivity in detecting cancer. In one study, it was determined that the use of swabs was ineffective in identifying cancer in as many as 92% of anal cancer patients. In addition, swabs can be uncomfortable to patients and, therefore, can provide motivation for such patients to avoid an anal exam.
In view of the above discussion, it can be appreciated that it would be desirable to have an alternative device for collecting cells from the anus for the purpose of screening for anal cancer.